package cli import ( "bytes" "encoding/base64" "encoding/hex" "encoding/json" "errors" "fmt" "io/ioutil" "math/big" "os" "strconv" "strings" "text/tabwriter" "github.com/abiosoft/readline" "github.com/nspcc-dev/neo-go/pkg/compiler" "github.com/nspcc-dev/neo-go/pkg/encoding/address" "github.com/nspcc-dev/neo-go/pkg/encoding/bigint" "github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag" "github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest" "github.com/nspcc-dev/neo-go/pkg/util" "github.com/nspcc-dev/neo-go/pkg/vm" "github.com/nspcc-dev/neo-go/pkg/vm/stackitem" "gopkg.in/abiosoft/ishell.v2" ) const ( vmKey = "vm" manifestKey = "manifest" boolType = "bool" boolFalse = "false" boolTrue = "true" intType = "int" stringType = "string" exitFunc = "exitFunc" ) var commands = []*ishell.Cmd{ { Name: "exit", Help: "Exit the VM prompt", LongHelp: "Exit the VM prompt", Func: handleExit, }, { Name: "ip", Help: "Show current instruction", LongHelp: "Show current instruction", Func: handleIP, }, { Name: "break", Help: "Place a breakpoint", LongHelp: `Usage: break is mandatory parameter, example: > break 12`, Func: handleBreak, }, { Name: "estack", Help: "Show evaluation stack contents", LongHelp: "Show evaluation stack contents", Func: handleXStack, }, { Name: "astack", Help: "Show alt stack contents", LongHelp: "Show alt stack contents", Func: handleXStack, }, { Name: "istack", Help: "Show invocation stack contents", LongHelp: "Show invocation stack contents", Func: handleXStack, }, { Name: "loadnef", Help: "Load a NEF-consistent script into the VM", LongHelp: `Usage: loadnef both parameters are mandatory, example: > loadnef /path/to/script.nef /path/to/manifest.json`, Func: handleLoadNEF, }, { Name: "loadbase64", Help: "Load a base64-encoded script string into the VM", LongHelp: `Usage: loadbase64 is mandatory parameter, example: > loadbase64 AwAQpdToAAAADBQV9ehtQR1OrVZVhtHtoUHRfoE+agwUzmFvf3Rhfg/EuAVYOvJgKiON9j8TwAwIdHJhbnNmZXIMFDt9NxHG8Mz5sdypA9G/odiW8SOMQWJ9W1I4`, Func: handleLoadBase64, }, { Name: "loadhex", Help: "Load a hex-encoded script string into the VM", LongHelp: `Usage: loadhex is mandatory parameter, example: > loadhex 0c0c48656c6c6f20776f726c6421`, Func: handleLoadHex, }, { Name: "loadgo", Help: "Compile and load a Go file with the manifest into the VM", LongHelp: `Usage: loadgo is mandatory parameter, example: > loadgo /path/to/file.go`, Func: handleLoadGo, }, { Name: "parse", Help: "Parse provided argument and convert it into other possible formats", LongHelp: `Usage: parse is an argument which is tried to be interpreted as an item of different types and converted to other formats. Strings are escaped and output in quotes.`, Func: handleParse, }, { Name: "run", Help: "Execute the current loaded script", LongHelp: `Usage: run [ [...]] is a contract method, specified in manifest (and it can't be 'help' at the moment). It can be '_' which will push parameters onto the stack and execute from the current offset. is a parameter (can be repeated multiple times) that can be specified as :, where type can be: '` + boolType + `': supports '` + boolFalse + `' and '` + boolTrue + `' values '` + intType + `': supports integers as values '` + stringType + `': supports strings as values (that are pushed as a byte array values to the stack) or can be just , for which the type will be detected automatically following these rules: '` + boolTrue + `' and '` + boolFalse + `' are treated as respective boolean values, everything that can be converted to integer is treated as integer and everything else is treated like a string. Example: > run put ` + stringType + `:"Something to put"`, Func: handleRun, }, { Name: "cont", Help: "Continue execution of the current loaded script", LongHelp: "Continue execution of the current loaded script", Func: handleCont, }, { Name: "step", Help: "Step (n) instruction in the program", LongHelp: `Usage: step [] is optional parameter to specify number of instructions to run, example: > step 10`, Func: handleStep, }, { Name: "stepinto", Help: "Stepinto instruction to take in the debugger", LongHelp: `Usage: stepInto example: > stepinto`, Func: handleStepInto, }, { Name: "stepout", Help: "Stepout instruction to take in the debugger", LongHelp: `Usage: stepOut example: > stepout`, Func: handleStepOut, }, { Name: "stepover", Help: "Stepover instruction to take in the debugger", LongHelp: `Usage: stepOver example: > stepover`, Func: handleStepOver, }, { Name: "ops", Help: "Dump opcodes of the current loaded program", LongHelp: "Dump opcodes of the current loaded program", Func: handleOps, }, } // Various errors. var ( ErrMissingParameter = errors.New("missing argument") ErrInvalidParameter = errors.New("can't parse argument") ) // VMCLI object for interacting with the VM. type VMCLI struct { vm *vm.VM shell *ishell.Shell // printLogo specifies if logo is printed. printLogo bool } // New returns a new VMCLI object. func New() *VMCLI { return NewWithConfig(true, os.Exit, &readline.Config{ Prompt: ">>>", }) } // NewWithConfig returns new VMCLI instance using provided config. func NewWithConfig(printLogo bool, onExit func(int), c *readline.Config) *VMCLI { vmcli := VMCLI{ vm: vm.New(), shell: ishell.NewWithConfig(c), printLogo: printLogo, } vmcli.shell.Set(vmKey, vmcli.vm) vmcli.shell.Set(manifestKey, new(manifest.Manifest)) vmcli.shell.Set(exitFunc, onExit) for _, c := range commands { vmcli.shell.AddCmd(c) } changePrompt(vmcli.shell, vmcli.vm) return &vmcli } func getVMFromContext(c *ishell.Context) *vm.VM { return c.Get(vmKey).(*vm.VM) } func getManifestFromContext(c *ishell.Context) *manifest.Manifest { return c.Get(manifestKey).(*manifest.Manifest) } func setManifestInContext(c *ishell.Context, m *manifest.Manifest) { old := getManifestFromContext(c) *old = *m } func checkVMIsReady(c *ishell.Context) bool { v := getVMFromContext(c) if v == nil || !v.Ready() { c.Err(errors.New("VM is not ready: no program loaded")) return false } return true } func handleExit(c *ishell.Context) { c.Println("Bye!") c.Get(exitFunc).(func(int))(0) } func handleIP(c *ishell.Context) { if !checkVMIsReady(c) { return } v := getVMFromContext(c) ctx := v.Context() if ctx.NextIP() < ctx.LenInstr() { ip, opcode := v.Context().NextInstr() c.Printf("instruction pointer at %d (%s)\n", ip, opcode) } else { c.Println("execution has finished") } } func handleBreak(c *ishell.Context) { if !checkVMIsReady(c) { return } v := getVMFromContext(c) if len(c.Args) != 1 { c.Err(fmt.Errorf("%w: ", ErrMissingParameter)) return } n, err := strconv.Atoi(c.Args[0]) if err != nil { c.Err(fmt.Errorf("%w: %v", ErrInvalidParameter, err)) return } v.AddBreakPoint(n) c.Printf("breakpoint added at instruction %d\n", n) } func handleXStack(c *ishell.Context) { v := getVMFromContext(c) c.Println(v.Stack(c.Cmd.Name)) } func handleLoadNEF(c *ishell.Context) { v := getVMFromContext(c) if len(c.Args) < 2 { c.Err(fmt.Errorf("%w: ", ErrMissingParameter)) return } if err := v.LoadFileWithFlags(c.Args[0], callflag.All); err != nil { c.Err(err) return } m, err := getManifestFromFile(c.Args[1]) if err != nil { c.Err(err) return } c.Printf("READY: loaded %d instructions\n", v.Context().LenInstr()) setManifestInContext(c, m) changePrompt(c, v) } func handleLoadBase64(c *ishell.Context) { v := getVMFromContext(c) if len(c.Args) < 1 { c.Err(fmt.Errorf("%w: ", ErrMissingParameter)) return } b, err := base64.StdEncoding.DecodeString(c.Args[0]) if err != nil { c.Err(fmt.Errorf("%w: %v", ErrInvalidParameter, err)) return } v.LoadWithFlags(b, callflag.All) c.Printf("READY: loaded %d instructions\n", v.Context().LenInstr()) changePrompt(c, v) } func handleLoadHex(c *ishell.Context) { v := getVMFromContext(c) if len(c.Args) < 1 { c.Err(fmt.Errorf("%w: ", ErrMissingParameter)) return } b, err := hex.DecodeString(c.Args[0]) if err != nil { c.Err(fmt.Errorf("%w: %v", ErrInvalidParameter, err)) return } v.LoadWithFlags(b, callflag.All) c.Printf("READY: loaded %d instructions\n", v.Context().LenInstr()) changePrompt(c, v) } func handleLoadGo(c *ishell.Context) { v := getVMFromContext(c) if len(c.Args) < 1 { c.Err(fmt.Errorf("%w: ", ErrMissingParameter)) return } b, di, err := compiler.CompileWithDebugInfo(c.Args[0], nil) if err != nil { c.Err(err) return } // Don't perform checks, just load. m, err := di.ConvertToManifest(&compiler.Options{}) if err != nil { c.Err(fmt.Errorf("can't create manifest: %w", err)) return } setManifestInContext(c, m) v.LoadWithFlags(b, callflag.All) c.Printf("READY: loaded %d instructions\n", v.Context().LenInstr()) changePrompt(c, v) } func getManifestFromFile(name string) (*manifest.Manifest, error) { bs, err := ioutil.ReadFile(name) if err != nil { return nil, fmt.Errorf("%w: can't read manifest", ErrInvalidParameter) } var m manifest.Manifest if err := json.Unmarshal(bs, &m); err != nil { return nil, fmt.Errorf("%w: can't unmarshal manifest", ErrInvalidParameter) } return &m, nil } func handleRun(c *ishell.Context) { v := getVMFromContext(c) m := getManifestFromContext(c) if len(c.Args) != 0 { var ( params []stackitem.Item offset int err error runCurrent = c.Args[0] != "_" ) params, err = parseArgs(c.Args[1:]) if err != nil { c.Err(err) return } if runCurrent { md := m.ABI.GetMethod(c.Args[0], len(params)) if md == nil { c.Err(fmt.Errorf("%w: method not found", ErrInvalidParameter)) return } offset = md.Offset } for i := len(params) - 1; i >= 0; i-- { v.Estack().PushVal(params[i]) } if runCurrent { v.Jump(v.Context(), offset) if initMD := m.ABI.GetMethod(manifest.MethodInit, 0); initMD != nil { v.Call(v.Context(), initMD.Offset) } } } runVMWithHandling(c, v) changePrompt(c, v) } // runVMWithHandling runs VM with handling errors and additional state messages. func runVMWithHandling(c *ishell.Context, v *vm.VM) { err := v.Run() if err != nil { c.Err(err) } var message string switch { case v.HasFailed(): message = "" // the error will be printed on return case v.HasHalted(): message = v.Stack("estack") case v.AtBreakpoint(): ctx := v.Context() if ctx.NextIP() < ctx.LenInstr() { i, op := ctx.NextInstr() message = fmt.Sprintf("at breakpoint %d (%s)", i, op) } else { message = "execution has finished" } } if message != "" { c.Println(message) } } func handleCont(c *ishell.Context) { if !checkVMIsReady(c) { return } v := getVMFromContext(c) runVMWithHandling(c, v) changePrompt(c, v) } func handleStep(c *ishell.Context) { var ( n = 1 err error ) if !checkVMIsReady(c) { return } v := getVMFromContext(c) if len(c.Args) > 0 { n, err = strconv.Atoi(c.Args[0]) if err != nil { c.Err(fmt.Errorf("%w: %v", ErrInvalidParameter, err)) return } } v.AddBreakPointRel(n) runVMWithHandling(c, v) changePrompt(c, v) } func handleStepInto(c *ishell.Context) { handleStepType(c, "into") } func handleStepOut(c *ishell.Context) { handleStepType(c, "out") } func handleStepOver(c *ishell.Context) { handleStepType(c, "over") } func handleStepType(c *ishell.Context, stepType string) { if !checkVMIsReady(c) { return } v := getVMFromContext(c) var err error switch stepType { case "into": err = v.StepInto() case "out": err = v.StepOut() case "over": err = v.StepOver() } if err != nil { c.Err(err) } else { handleIP(c) } changePrompt(c, v) } func handleOps(c *ishell.Context) { if !checkVMIsReady(c) { return } v := getVMFromContext(c) out := bytes.NewBuffer(nil) v.PrintOps(out) c.Println(out.String()) } func changePrompt(c ishell.Actions, v *vm.VM) { if v.Ready() && v.Context().NextIP() >= 0 && v.Context().NextIP() < v.Context().LenInstr() { c.SetPrompt(fmt.Sprintf("NEO-GO-VM %d > ", v.Context().NextIP())) } else { c.SetPrompt("NEO-GO-VM > ") } } // Run waits for user input from Stdin and executes the passed command. func (c *VMCLI) Run() error { if c.printLogo { printLogo(c.shell) } c.shell.Run() return nil } func handleParse(c *ishell.Context) { res, err := Parse(c.Args) if err != nil { c.Err(err) return } c.Print(res) } // Parse converts it's argument to other formats. func Parse(args []string) (string, error) { if len(args) < 1 { return "", ErrMissingParameter } arg := args[0] buf := bytes.NewBuffer(nil) if val, err := strconv.ParseInt(arg, 10, 64); err == nil { bs := bigint.ToBytes(big.NewInt(val)) buf.WriteString(fmt.Sprintf("Integer to Hex\t%s\n", hex.EncodeToString(bs))) buf.WriteString(fmt.Sprintf("Integer to Base64\t%s\n", base64.StdEncoding.EncodeToString(bs))) } noX := strings.TrimPrefix(arg, "0x") if rawStr, err := hex.DecodeString(noX); err == nil { if val, err := util.Uint160DecodeBytesBE(rawStr); err == nil { buf.WriteString(fmt.Sprintf("BE ScriptHash to Address\t%s\n", address.Uint160ToString(val))) buf.WriteString(fmt.Sprintf("LE ScriptHash to Address\t%s\n", address.Uint160ToString(val.Reverse()))) } buf.WriteString(fmt.Sprintf("Hex to String\t%s\n", fmt.Sprintf("%q", string(rawStr)))) buf.WriteString(fmt.Sprintf("Hex to Integer\t%s\n", bigint.FromBytes(rawStr))) buf.WriteString(fmt.Sprintf("Swap Endianness\t%s\n", hex.EncodeToString(util.ArrayReverse(rawStr)))) } if addr, err := address.StringToUint160(arg); err == nil { buf.WriteString(fmt.Sprintf("Address to BE ScriptHash\t%s\n", addr)) buf.WriteString(fmt.Sprintf("Address to LE ScriptHash\t%s\n", addr.Reverse())) buf.WriteString(fmt.Sprintf("Address to Base64 (BE)\t%s\n", base64.StdEncoding.EncodeToString(addr.BytesBE()))) buf.WriteString(fmt.Sprintf("Address to Base64 (LE)\t%s\n", base64.StdEncoding.EncodeToString(addr.BytesLE()))) } if rawStr, err := base64.StdEncoding.DecodeString(arg); err == nil { buf.WriteString(fmt.Sprintf("Base64 to String\t%s\n", fmt.Sprintf("%q", string(rawStr)))) buf.WriteString(fmt.Sprintf("Base64 to BigInteger\t%s\n", bigint.FromBytes(rawStr))) } buf.WriteString(fmt.Sprintf("String to Hex\t%s\n", hex.EncodeToString([]byte(arg)))) buf.WriteString(fmt.Sprintf("String to Base64\t%s\n", base64.StdEncoding.EncodeToString([]byte(arg)))) out := buf.Bytes() buf = bytes.NewBuffer(nil) w := tabwriter.NewWriter(buf, 0, 4, 4, '\t', 0) if _, err := w.Write(out); err != nil { return "", err } if err := w.Flush(); err != nil { return "", err } return buf.String(), nil } func parseArgs(args []string) ([]stackitem.Item, error) { items := make([]stackitem.Item, len(args)) for i, arg := range args { var typ, value string typeAndVal := strings.Split(arg, ":") if len(typeAndVal) < 2 { if typeAndVal[0] == boolFalse || typeAndVal[0] == boolTrue { typ = boolType } else if _, err := strconv.Atoi(typeAndVal[0]); err == nil { typ = intType } else { typ = stringType } value = typeAndVal[0] } else { typ = typeAndVal[0] value = typeAndVal[1] } switch typ { case boolType: if value == boolFalse { items[i] = stackitem.NewBool(false) } else if value == boolTrue { items[i] = stackitem.NewBool(true) } else { return nil, fmt.Errorf("%w: invalid bool value", ErrInvalidParameter) } case intType: val, err := strconv.ParseInt(value, 10, 64) if err != nil { return nil, fmt.Errorf("%w: invalid integer value", ErrInvalidParameter) } items[i] = stackitem.NewBigInteger(big.NewInt(val)) case stringType: items[i] = stackitem.NewByteArray([]byte(value)) } } return items, nil } const logo = ` _ ____________ __________ _ ____ ___ / | / / ____/ __ \ / ____/ __ \ | | / / |/ / / |/ / __/ / / / /_____/ / __/ / / /____| | / / /|_/ / / /| / /___/ /_/ /_____/ /_/ / /_/ /_____/ |/ / / / / /_/ |_/_____/\____/ \____/\____/ |___/_/ /_/ ` func printLogo(c *ishell.Shell) { c.Print(logo) c.Println() c.Println() }